Closure of patent foramen ovale versus medical therapy after cryptogenic stroke

Percutaneous closure of patent foramen ovale: “Closed” door after the last randomized trials?

Patent foramen ovale (PFO) percutaneous closure has previously been an accepted intervention for the prevention of recurrent cryptogenic stroke on the basis of observational studies. However, randomized trials have been lacking until now. Three recently published randomized trials (CLOSURE I, PC and RESPECT) do not demonstrate the superiority of this intervention versus optimal medical therapy, therefore making this practice questionable. Nonetheless, these trials have had certain pitfalls, mainly a lower than initially estimated number of patients recruited, therefore lacking sufficient statistical power. On the other hand, different closure devices were used in the three trials. In two of them (PC and RESPECT), the Amplatzer PFO Occluder was used and the STARflex device was used in the other one (CLOSURE I). Taken altogether, a meta-analysis of these three trials does not demonstrate a statistically significant benefit of percutaneous PFO closure (1.9% vs 2.9%; P = 0.11). However, if we analyze only the PC and RESPECT trials together, in which the Amplatzer PFO Occluder was used, a statistically significant benefit of percutaneous PFO closure is observed (1.4% vs 3.0%, P = 0.04). In conclusion, our interpretation of these trials is that the use of a dedicated, specifically designed Amplatzer PFO device could possibly reduce the risk of stroke in patients with PFO and cryptogenic stroke. This consideration equally applies to patients who have no contraindications for anticoagulant or antithrombotic therapy.

Cardiac right-to-left shunt subtypes in Chinese patients with cryptogenic strokes: a multicenter case-control study

BACKGROUND AND PURPOSE

Data on the possible association between cardiac right-to-left shunt (RLS) and cryptogenic stroke are lacking in Asians. RLS and its subtypes in Chinese cryptogenic stroke patients were investigated.

METHODS

Patients (n = 153, mean age 42 ± 10 years, 81 male) with cryptogenic stroke from four medical centers in China and 135 healthy volunteers (mean age 34 ± 8 years, 54 male) were recruited. Contrast transcranial Doppler was used to assess the prevalence of RLS. A three-level RLS categorization was applied as follows: none, 0 microbubbles (MBs); small, 1-25 MBs; and large, >25 MBs. RLS was considered latent if it occurred only after the Valsalva maneuver or permanent when it occurred also during normal respiration.

RESULTS

Overall, RLS (P = 0.02), large RLS (P < 0.001) and permanent RLS (P = 0.02) were more frequently detected in patients with cryptogenic stroke than in healthy volunteers. The prevalences of small RLS and latent RLS in the two groups were similar (22% vs. 21% and 11% vs. 10%, respectively). The proportion of large RLSs amongst the subjects with RLS was much higher in the patient group than in healthy volunteers (45% vs. 18%, P < 0.001), whilst the proportion of permanent RLS was similar (72% vs. 64%, P = 0.11). Most large RLSs in the patient group (22/27, 81%) were permanent RLSs.

CONCLUSIONS

Cardiac RLS is associated with cryptogenic stroke in Chinese. However, the higher prevalence of overall RLS in the patient group was mainly due to the increased proportion of large RLSs. The results only support large RLSs as a pathological condition.

[Heart or brain? Problem patients at the interface between cardiology and neurology]

A large number of patients fall into a category at the interface between heart or brain and are expected to require thorough clinical knowledge from both the cardiological as well as the neurological point of view for further patient-oriented treatment. The current article therefore addresses this important issue and aims to provide important information for clinical decision making for those patients at the interface between heart and brain. Due to the clinical impact, patients with carotid stenosis, a patent foramen ovale or non-valvular atrial fibrillation are described in more detail in this article.

Secondary prevention of ischaemic stroke

In spite of a documented reduction in incidence in high-income countries over the last decades, stroke is still a leading cause of death and disability worldwide. With the ageing of the population stroke-related economic burden is expected to increase, because of residual disability and its complications, such as cognitive impairment, high risk of falls and fractures, depression and epilepsy. Furthermore, because of the substantial rate of early and long-term vascular recurrences after the first event, secondary prevention after cerebral ischaemia is a crucial issue. This is even more important after minor stroke and transient ischaemic attack (TIA), in order to reduce the risk of potentially more severe and disabling events. To accomplish this aim, acute long-term medical and surgical treatments as well as lifestyle modifications are strongly recommended. However, apart from the well-established indications to thrombolysis, studies in acute phase after a first stroke or TIA are scarce and evidence is lacking. More trials are available for long-term secondary prevention with different classes of drugs, including antithrombotic medications for ischaemic events of arterial and cardiac origin, especially related to atrial fibrillation (antiplatelets and anticoagulants, respectively), lipid lowering agents (mainly statins), blood pressure lowering drugs, surgical and endovascular revascularization procedures.

Amplatzer PFO occluder device may prevent recurrent stroke in patients with patent foramen ovale and cryptogenic stroke: a meta-analysis of randomised trials

OBJECTIVE

To review efficacy of percutaneous closure of patent foramen ovale compared with medical therapy in prevention of recurrent strokes in patients with cryptogenic stroke.

METHODS AND RESULTS

Electronic databases; PUBMED, EMBASE, Cochrane registry and web of knowledge were searched for relevant studies. In three randomised clinical trials involving 2303 participants, risk of the recurrent strokes (pooled HR 0.62, 95% CI=0.36-1.07, P=0.09, I(2) =10%) did not show benefit with device closure when compared with medical therapy group on meta-analysis of all three trials. However, on sensitivity analysis in trials using Amplatzer PFO occluder device, the closure of PFO was associated with significantly lower recurrent strokes (pooled HR=0.44, 95% CI=0.21-0.94, P=0.03, I(2)=0%) compared with medical therapy.

CONCLUSION

The closure of PFO with Amplatzer PFO occluder device was associated with significant reduction in recurrent strokes in patients with cryptogenic stroke and patent foramen ovale. The better outcome in prevention of secondary stroke in patients with cryptogenic stroke and PFO may be associated with type of closure device used.

Transcatheter patent foramen ovale closure versus medical therapy for cryptogenic stroke: a meta-analysis of randomized clinical trials

BACKGROUND

There is an association between cryptogenic stroke and patent foramen ovale (PFO). The optimal treatment strategy for secondary prevention remains unclear. The purpose of this study was to analyze aggregate data examining the safety and efficacy of transcatheter device closure versus standard medical therapy in patients with PFO and cryptogenic stroke.

METHODS

A search of published data identified 3 randomized clinical trials for inclusion. The primary outcome was a composite end-point of death, stroke and transient-ischemic attack (TIA). Pre-defined subgroup analysis was performed with respect to baseline characteristics including age, sex, atrial septal aneurysm and shunt size. Data was synthesized using a random effects model and results presented as hazard ratios (HRs) with 95% confidence intervals (CIs).

RESULTS

A cohort of 2,303 patients with a history of cryptogenic stroke and PFO were randomized to device closure (n = 1150) and medical therapy (n = 1153). Mean follow-up was 2.5 years. Transcatheter closure was not superior to medical therapy in the secondary prevention of stroke or TIA in intention-to-treat analysis (HR: 0.66, 95% CI: 0.43 to 1.01; p = 0.056). However, the results were statistically significant using per-protocol analysis (HR: 0.64, 95% CI: 0.41 to 0.98; p = 0.043). Males had significant benefit with device closure (HR: 0.48, 95% CI: 0.24 to 0.96; p = 0.038).

CONCLUSIONS

In this meta-analysis, using intention-to-treat analysis, transcatheter device closure of PFO was not superior to standard medical therapy in the secondary prevention of cryptogenic stroke. Transcatheter closure was superior using per-protocol analysis.

Advances and challenges in treatment and prevention of ischemic stroke

We review recent advances in the treatment and prevention of acute ischemic stroke, including the current state of endovascular therapy, in light of 5 randomized controlled trials published this past year. Although no benefit of endovascular therapy over intravenous (IV) recombinant tissue plasminogen activator (rt-PA) has been demonstrated, endovascular therapy is an appropriate treatment for acute ischemic stroke patients within the t-PA window who are ineligible for IV t-PA but have a large vascular occlusion. These trials reveal promises and current limitations of endovascular therapy, and comparison of reperfusion therapies remains an important area of research. One common theme is the strong association between a faster time to reperfusion, improved outcome, and reduced mortality. Primary and secondary stroke prevention trials emphasize the importance of aggressive management of medical risk factors as part of any preventative strategy. New oral anticoagulants, for example, offer cost-effective risk reduction in patients with atrial fibrillation, and may represent an opportunity for those with cryptogenic stroke. We highlight areas of unmet need and promising research in stroke, including the need to deliver proven therapies to more patients, and the need to recruit patients into clinical trials that better define the role of endovascular and other stroke therapies. Finally, improvement in strategies to recover speech, cognition, and motor function has the potential to benefit far more stroke patients than any acute stroke therapy, and represents the greatest opportunity for research in the coming century.

Seven-year follow-up of percutaneous closure of patent foramen ovale

Background

Observational studies favor percutaneous closure of patent foramen ovale (PFO) over medical treatment to reduce recurrent stroke while randomized trials fail to demonstrate significant superiority of percutaneous PFO closure. Few long-term studies are available post PFO closure. This study reports long-term clinical outcomes after percutaneous PFO closure.

Methods

Between 1997 and 2006, 86 consecutive eligible patients with cerebrovascular events, presumably related to PFO, underwent percutaneous PFO closure. All 86 patients were invited to a long-term follow-up, which was carried out during 2011 and 2012.

Results

Percutaneous PFO closure was successfully performed in 85 of 86 patients. The follow-up rate was 100%. No cardiovascular or cerebrovascular deaths occurred. Two patients (both women) died from lung cancer during follow-up. Follow-up visits were conducted for 64 patients and the remaining 20 patients were followed up by phone. The mean follow-up time was 7.3 years (5 to 12.4 years). Mean age at PFO closure was 49 years. One patient had a minor stroke one month after PFO closure and a transient ischemic attack (TIA) two years afterwards. One other patient suffered from a TIA six years after closure. No long-term device-related complications were observed.

Conclusions

Percutaneous PFO closure was associated with very low risk of recurrent stroke and is suitable in most patients. We observed no mortality and no long-term device-related complications related to PFO closure, indicating that percutaneous PFO closure is a safe and efficient treatment even in the long term.

Silent cerebral infarcts associated with cardiac disease and procedures

The occurrence of clinically silent cerebral infarcts (SCIs) in individuals affected by cardiac disease and after invasive cardiac procedures is frequently reported. Indeed, atrial fibrillation, left ventricular thrombus formation, cardiomyopathy, and patent foramen ovale have all been associated with SCIs. Furthermore, postprocedural SCIs have been observed after left cardiac catheterization, transcatheter aortic valve implantation, CABG surgery, pulmonary vein isolation, and closure of patent foramen ovale. Such SCIs are often described as precursors to symptomatic stroke and are associated with cognitive decline, dementia, and depression. Increased recognition of SCIs might advance our understanding of their relationship with heart disease and invasive cardiac procedures, facilitate further improvement of therapies or techniques aimed at preventing their occurrence and, therefore, decrease the risk of adverse neurological outcomes. In this Review, we provide an overview of the occurrence and clinical significance of, and the available diagnostic modalities for, SCIs related to cardiac disease and associated invasive cardiac procedures.

Safety and efficacy of device closure for patent foramen ovale for secondary prevention of neurological events: Comprehensive systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Controversy persists regarding the management of patients with cryptogenic stroke and patent foramen ovale (PFO). We performed a meta-analysis of randomized controlled trials comparing PFO closure with medical therapy.

METHODS AND RESULTS

A prospective protocol was developed and registered using the following data sources: PubMed, Cochrane Register of Controlled Trials, conference proceedings, and Internet-based resources of clinical trials. Primary analyses were performed using the intention-to-treat method. Three randomized trials comparing percutaneous PFO closure vs. medical therapy for secondary prevention of embolic neurological events formed the data set. Baseline characteristics were similar. During long-term follow-up, the pooled incidence of the primary endpoint (composite of stroke, death, or fatal stroke) was 3.4% in the PFO closure arm and 4.8% in the medical therapy group [risk-reduction (RR) 0.7 (0.48-1.06); p=0.09]. The incidence of recurrent neurological events (secondary endpoint) was 1.7% for PFO closure and 2.7% for medical therapy [RR 0.66 (0.35-1.24), p=0.19]. There was no difference in terms of death or adverse events between the two groups.

CONCLUSIONS

While this meta-analysis of randomized clinical trials demonstrated no statistical significance in comparison to medical therapy, there was a trend towards overall improvement in outcomes in the PFO closure group.

Multidisciplinary management of patent foramen ovale (PFO) and cryptogenic stroke/TIA

PURPOSE

Patent foramen ovale (PFO) has been implicated as a risk factor for cryptogenic ischemic stroke (CS). However, there is still a lack of widely accepted, undisputed indications for PFO closure. The present study describes the concept of the multidisciplinary PFO conference and a decision making process for closure versus no closure that was developed into a formalized clinical algorithm, and presents the results of implementing these, in terms of number and proportion of PFO closures as well as repeat referrals.

DESIGN

Five specialists in neurology, cardiology, internal medicine, thromboembolism, and echocardiography evaluated the clinical data of 311 patients at PFO conferences during 2006 to 2009. The main criteria for closure were patients with first-ever CS with PFO and atrial septal aneurysm, or patients with recurrent CS and PFO without atrial septal aneurysm.

RESULTS

A total of 143 patients (46%) were accepted for closure and 167 patients were rejected. Patients accepted for closure were younger (mean 50 years versus 58 years) (P < 0.001). The acceptance rate for PFO closure was similar throughout these years, with an average of 45%. Three of 167 patients (1.8%) initially rejected for PFO closure were re-referred due to recurrent stroke, and the PFO closure was subsequently performed.

CONCLUSION

The acceptance rate of less than 50% in the present study underscores the complex relationship between CS and PFO. Whatever the criteria used for PFO closure, any unit caring for these patients needs to have a rigorous process to avoid overtreatment as well as undertreatment and to ensure that personal preferences and economic incentives do not steer the selection process. Our algorithm provides a stable acceptance rate and a low rate of repeat referrals.

Recognition and management of stroke in young adults and adolescents

Approximately 15% of all ischemic strokes (IS) occur in young adults and adolescents. To date, only limited prior public health and research efforts have specifically addressed stroke in the young. Early diagnosis remains challenging because of the lack of awareness and the relative infrequency of stroke compared with stroke mimics. Moreover, the causes of IS in the young are heterogeneous and can be relatively uncommon, resulting in uncertainties about diagnostic evaluation and cause-specific management. Emerging data have raised public health concerns about the increasing prevalence of traditional vascular risk factors in young individuals, and their potential role in increasing the risk of IS, stroke recurrence, and poststroke mortality. These issues make it important to formulate and enact strategies to increase both awareness and access to resources for young stroke patients, their caregivers and families, and health care professionals. The American Academy of Neurology recently convened an expert panel to develop a consensus document concerning the recognition, evaluation, and management of IS in young adults and adolescents. The report of the consensus panel is presented herein.

Patent foramen ovale and cryptogenic stroke: the hole story

Despite 3 recent randomized clinical trials, the management of patients with cryptogenic stroke and patent foramen ovale remains unsettled. The primary results of Evaluation of the STARFlex Septal Closure System in Patients with a Stroke and/or Transient Ischemic Attack due to Presumed Paradoxical Embolism Through a Patent Foramen Ovale (CLOSURE), Percutaneous Closure of Patent Foramen Ovale in Cryptogenic Stroke (PC), and Randomized Evaluation of Recurrent Stroke Comparing PFO Closure to Established Current Standard of Care Treatment (RESPECT) were the same; the intent to treat analysis for the primary end point in all 3 trials failed to demonstrate superiority of device closure compared with medical therapy. CLOSURE put the brakes on indiscriminate device closure of patent foramen ovales in patients with cryptogenic stroke or transient ischemic attack. RESPECT suggested, but did not prove, that highly selected patients without vascular risk factors, with a cortical infarct on baseline magnetic resonance imaging and a substantial patent foramen ovale shunt may benefit from the Amplatzer device during a multiple-year period. In the absence of definitive clinical trial results, the precise definition of which patient subgroups should be considered for patent foramen ovale device closure should be agreed to by the stakeholder societies and the Food and Drug Administration.

Patent foramen ovale transcatheter closure vs. medical therapy on recurrent vascular events: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

In patients with cryptogenic stroke, transcatheter (TC) closure of a patent foramen ovale (PFO) has not been shown to better prevent recurrent vascular events than medical therapy. However, randomized controlled trials (RCT) to date have included few vascular events, and lack of power has been raised as an important concern.

OBJECTIVE

To conduct a systematic review and meta-analysis of existing RCT published studies assessing the recurrence of vascular events after TC PFO closure when compared to medical therapy.

METHODS

Using the search terms "patent foramen ovale", "PFO", "stroke", "percutaneous closure" and "transcatheter closure", Medline, Pubmed, Embase, and Cochrane databases were reviewed from inception through April 2013, with no language restrictions. Only studies in adult humans were considered. Additional references were obtained from the bibliographies of studies reviewed. The following criteria were used for study selection: 1) randomized controlled trial, 2) subjects were adult patients with cryptogenic stroke who were randomized to TC PFO closure or medical treatment (antiplatelet therapy and/or anticoagulation), and 3) reported outcomes included cardiac death, all death, stroke, transient ischemic attack, and peripheral embolism. Methodological and descriptive data, adverse events (including raw data and risk estimates), as well as procedural success and complications were abstracted in duplicate from each study independently, and agreement was tested. We followed rigorously the recommended guidelines for reporting and conducting and assessing quality of meta-analysis of RCT. The primary endpoints pre-specified in advance were recurrent vascular events, and composite endpoint of death, and recurrent vascular events.

RESULTS

Three studies were identified as meeting selection criteria. These included a total of 2,303 patients, with 1,150 patients randomized to TC PFO closure and 1,153 patients randomized to medical therapy. Mean follow-up was 3.5 years. Baseline characteristics (age, sex, and cardiovascular risk factors) were similar across studies. Intention-to-treat analyses showed a statistically significant risk reduction in stroke and/or transient ischemic attack in the TC PFO closure group when compared to medical treatment, pooled HR = 0.59, 95%CI (0.36-0.97), P = 0.04. The combined outcome of death, and vascular events, showed a borderline statistically significant benefit for TC PFO closure when compared to medical treatment, pooled HR = 0.67, 95%CI (0.44-1.00), P = 0.05 Subjects with a substantial PFO shunt seem to benefit the most with TC PFO closure, pooled HR = 0.35, 95%CI (0.12-1.03), P = 0.06, however, it did not reach statistical significance.

CONCLUSION

These results suggest that in patients with cryptogenic stroke, TC PFO closure may be beneficial in reducing the risk of recurrent vascular events when compared to medical treatment. The benefit of TC PFO closure may be greater in patients with a substantial shunt.

Patent foramen ovale, subclinical cerebrovascular disease, and ischemic stroke in a population-based cohort

OBJECTIVES

The purpose of this study was to evaluate the relationship between patent foramen ovale (PFO), ischemic stroke, and subclinical cerebrovascular disease in the general population.

BACKGROUND

PFO is found more frequently in stroke patients than in stroke-free controls. However, the PFO-related stroke risk in the general population is not well established, and the relationship between PFO and silent brain infarcts (SBI) is not known.

METHODS

PFO presence was assessed by transthoracic echocardiography with saline contrast injection in 1,100 stroke-free individuals over age 39 of a community-based sample followed for a mean of 11 years. In addition, 360 participants underwent brain magnetic resonance imaging (MRI) for SBI detection. We evaluated the risk of stroke associated with PFO after adjusting for established stroke risk factors and examined the odds of having SBI among those with and without PFO.

RESULTS

PFO was present in 164 participants (14.9%). Over a mean follow-up of 11.0 ± 4.5 years, 111 ischemic strokes occurred (10.1%), 15 (9.2%) in the PFO+ and 96 (10.3%) in the PFO- groups. The 12.5-year cumulative risk of stroke was 10.1% (standard error: 2.5%) in the PFO+ and 10.4% (standard error: 1.1%) in the PFO- group (p = 0.46). The adjusted hazard ratio for PFO and stroke was 1.10 (95% confidence interval [CI]: 0.64 to 1.91). In the MRI subcohort, PFO was not associated with SBI (adjusted odds ratio: 1.15, 95% CI: 0.50 to 2.62).

CONCLUSIONS

In this community-based cohort, PFO was not associated with an increased risk of clinical stroke or subclinical cerebrovascular disease.

Percutaneous closure of patent foramen ovale in cryptogenic embolism

BACKGROUND

The options for secondary prevention of cryptogenic embolism in patients with patent foramen ovale are administration of antithrombotic medications or percutaneous closure of the patent foramen ovale. We investigated whether closure is superior to medical therapy.

METHODS

We performed a multicenter, superiority trial in 29 centers in Europe, Canada, Brazil, and Australia in which the assessors of end points were unaware of the study-group assignments. Patients with a patent foramen ovale and ischemic stroke, transient ischemic attack (TIA), or a peripheral thromboembolic event were randomly assigned to undergo closure of the patent foramen ovale with the Amplatzer PFO Occluder or to receive medical therapy. The primary end point was a composite of death, nonfatal stroke, TIA, or peripheral embolism. Analysis was performed on data for the intention-to-treat population.

RESULTS

The mean duration of follow-up was 4.1 years in the closure group and 4.0 years in the medical-therapy group. The primary end point occurred in 7 of the 204 patients (3.4%) in the closure group and in 11 of the 210 patients (5.2%) in the medical-therapy group (hazard ratio for closure vs. medical therapy, 0.63; 95% confidence interval [CI], 0.24 to 1.62; P=0.34). Nonfatal stroke occurred in 1 patient (0.5%) in the closure group and 5 patients (2.4%) in the medical-therapy group (hazard ratio, 0.20; 95% CI, 0.02 to 1.72; P=0.14), and TIA occurred in 5 patients (2.5%) and 7 patients (3.3%), respectively (hazard ratio, 0.71; 95% CI, 0.23 to 2.24; P=0.56).

CONCLUSIONS

Closure of a patent foramen ovale for secondary prevention of cryptogenic embolism did not result in a significant reduction in the risk of recurrent embolic events or death as compared with medical therapy. (Funded by St. Jude Medical; ClinicalTrials.gov number, NCT00166257.).

Leptin receptor action and mechanisms of leptin resistance

The adipose tissue-derived hormone leptin regulates energy balance and neuroendocrine function. Resistance to the appetite-suppressing effects of leptin is associated with common forms of obesity. Here, we review the mechanisms by which leptin activates intracellular signals and the roles that these signals play in leptin action in vivo. Furthermore, we discuss potential mechanisms of leptin resistance, specifically focusing on data regarding the neuroanatomical locus of leptin resistance and potential mechanisms by which expression of the suppressor of cytokine signaling-3 may impair leptin action.